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Homestake 2014 Geotechnical Observations <br />Pitch Reclamation Project Indian and Tie Camp Waste Rock Dumps <br />In 2014, the water level in IC 10600 increased in elevation by 11.8 feet between January <br />and June. This condition is similar to other piezometers in the Indian Dump, and reflects <br />the relatively high seasonal snow pack in the area. <br />Between June and December the water level in IC10600 dropped 10.0 feet to elevation <br />10352.77 feet amsl. Similar to IC10630, it appears that heavier than normal rainfall <br />during the summer months prevented this piezometer from dropping completely to its <br />January level. <br />c) "10725-10525" Level <br />Site Description: Identical to that of past reports for 1996 through 2013. The minor <br />overlap between this level and other bench designations reflects the original bench <br />configuration. The total dump thickness in IC10525 is approximately 229 feet at this <br />location. <br />2014 Observations: Piezometers IC10600 and IC10525 bound this area and similar to <br />piezometer IC10600, the 2014 water level in Piezometer IC10525 rose by 9.0 feet. This <br />compares with a 6.7 feet in 2013, 2.1 feet rise in 2012, 11.0 feet in 2011, 6.5 feet in 2010 <br />and 8.6 feet in 2009. The small rise in the water level in 2012 and 2013 reflected a <br />significantly reduced snow pack after several years with heavier snow pack. <br />Between June and December the water level in IC10525 dropped 8.2 feet to elevation <br />10295.2 feet amsl. Similar to other piezometers located at the Indian Rock Dump, it <br />appears that heavier than normal rainfall during the summer months prevented this <br />piezometer from dropping completely to its January level. <br />d) "10600 - 10400" Level <br />Site Description: Identical to that of past reports for 1996 through 2012. <br />2012 Observations: Piezometer IC10440 was located in this area of the rock dump; <br />however, it became non - functional in 1996. As such, Piezometer IC10525 is also <br />considered representative of this area of the rock dump and was described in the <br />previous section. <br />e) "10400-10370" Level <br />Site Description: Identical to that of past reports for 1997 through 2013. In 1997 <br />Homestake reconstructed the face of the permanent low -grade stockpile located on the <br />Indian Rock Dump. The purpose of the slope reconstruction was to reduce the potential <br />for infiltration and promote more rapid runoff from the slope. This reconstruction appears <br />to have effectively reduced seepage in this area. <br />2014 Observations: In 2011 replacement Piezometer IC1037OR was completed <br />approximately 67 feet to the west of the former location of IC10370. The piezometer was <br />terminated at 208 feet below ground surface (BGS) and completed with an 8 -inch steel <br />protective casing and set in concrete. Upon completion, a transducer was installed in <br />Piezometer IC10370R to assist in monitoring water levels. In 2012, the water level <br />elevation in Piezometer IC10370R rose by 7.1 feet in the spring and fell back to an <br />acceptable range by late summer. In 2013, the water level rose by 10.9 feet during the <br />spring snow melt and lost approximately five feet of that gain by the end of the year. <br />The increase in water level in 2013 compared with 2012 was attributable to heavier <br />snow pack and higher summer precipitation in 2013. The same trends were observed in <br />Homestake Pitch Reclamation Project Page 2 <br />2014 Annual Geotechnical Report December 23, 2014 <br />M- 1977 -004HR 2014AnnualGeotechnicalReportText _Final.doc <br />